Soul's Attendant

Whenever another creature enters, you may gain 1 life.

Aetherflux Reservoir

Whenever you cast a spell, you gain 1 life for each spell you've cast this turn.
Pay 50 life: Aetherflux Reservoir deals 50 damage to any target.

Remand

Counter target spell. If that spell is countered this way, put it into its owner's hand instead of into that player's graveyard.
Draw a card.

Profane Memento

Whenever a creature card is put into an opponent's graveyard from anywhere, you gain 1 life.

Zuran Orb

Perimeter Captain

Defender
Whenever a creature you control with defender blocks, you may gain 2 life.

Heliod, Sun-Crowned

Indestructible
As long as your devotion to white is less than five, Heliod isn't a creature.
Whenever you gain life, put a +1/+1 counter on target creature or enchantment you control.
{1}{W}: Another target creature gains lifelink until end of turn.

Luminous Phantom

Flying
Whenever another creature you control leaves the battlefield, you gain 1 life.
If Luminous Phantom would be put into a graveyard from anywhere, exile it instead.

Lunarch Veteran

Whenever another creature you control enters, you gain 1 life.
Disturb {1}{W} (You may cast this card from your graveyard transformed for its disturb cost.)

Lunarch Veteran // Luminous Phantom

Tablet of the Guilds

As Tablet of the Guilds enters, choose two colors.
Whenever you cast a spell, if it's at least one of the chosen colors, you gain 1 life for each of the chosen colors it is.

Prism Ring

As Prism Ring enters, choose a color.
Whenever you cast a spell of the chosen color, you gain 1 life.

Will, Scion of Peace

Vigilance
{T}: Spells you cast this turn that are white and/or blue cost {X} less to cast, where X is the amount of life you gained this turn. Activate only as a sorcery.

Pride Guardian

Defender
Whenever Pride Guardian blocks, you gain 3 life.

Hushbringer

Flying, lifelink
Creatures entering or dying don't cause abilities to trigger.

Kraken's Eye

Whenever a player casts a blue spell, you may gain 1 life.

Soulmender

Approach of the Second Sun

If this spell was cast from your hand and you've cast another spell named Approach of the Second Sun this game, you win the game. Otherwise, put Approach of the Second Sun into its owner's library seventh from the top and you gain 7 life.

Cleric Class

(Gain the next level as a sorcery to add its ability.)
If you would gain life, you gain that much life plus 1 instead.
{3}{W}: Level 2
Whenever you gain life, put a +1/+1 counter on target creature you control.
{4}{W}: Level 3
When this Class becomes level 3, return target creature card from your graveyard to the battlefield. You gain life equal to that creature's toughness.

Umezawa's Jitte

Whenever equipped creature deals combat damage, put two charge counters on Umezawa's Jitte.
Remove a charge counter from Umezawa's Jitte: Choose one —
• Equipped creature gets +2/+2 until end of turn.
• Target creature gets -1/-1 until end of turn.
• You gain 2 life.
Equip {2}

Angel's Feather

Whenever a player casts a white spell, you may gain 1 life.

Cathedral Sanctifier

When Cathedral Sanctifier enters, you gain 3 life.

Soul Warden

Whenever another creature enters, you gain 1 life.

Ajani's Welcome

Whenever a creature you control enters, you gain 1 life.

Martyr of Sands

{1}, Reveal X white cards from your hand, Sacrifice Martyr of Sands: You gain three times X life.

Walking Ballista

Walking Ballista enters with X +1/+1 counters on it.
{4}: Put a +1/+1 counter on Walking Ballista.
Remove a +1/+1 counter from Walking Ballista: It deals 1 damage to any target.